<!DOCTYPE html>
<html>
	<head>
		<meta charset="UTF-8">
		<title></title>
		<style type="text/css">
			.aaa{width:200px;height:200px;background-color:#BFA;
			     border:10px red solid;
			     
			     padding-top:100px;
			     padding-left:100px;}/*上内边距和左内边距分别为100px*/
			
			.bbb{width:100%;height:100%;background-color:yellow;}/*在aaa中设置一个子元素bbb，bbb占满aaa*/  
			
/*padding简写,和 border-width 规则一样*/	
           .ccc{width:200px;height:200px;background-color:#BFA;
			     
			     padding:20px 40px 60px;}	
			     
			     
			     
			
			
		</style>
	</head>
	<body>
		<div class="aaa">
			<div class="bbb"></div>
		</div>
		<br />
		
		<div class="ccc">
			<div class="bbb"></div>
		</div>
		
<!--padding会影响盒子可见框的大小，元素背景会延伸到内边距-->






	</body>
</html>
